Tripot universal joints are typically employed in automotive axial driveshafts and especially in front-wheel-drive vehicles between the transaxial  transaxle differential and the driving wheel. A typical tripot universal joint structure, which is also referred to herein below with regard to the present invention, is shown in FIGS. 1 and 2. The telescopic constant velocity joint such as the tripot should not only transmit the torque at various speeds, angles and telescopic positions but also prevent any vibrations of the engine from being transmitted through the joint and driveshaft to the driving wheel and the vehicle structure. In addition, when the universal joint operates at an angle it should not produce any oscillating axial excitation which may be capable of initiating vibrations in the driveshaft or in the structure of the vehicle.
U.S. Pat. No. 3,125,870 granted to Michael Orain, Mar. 24, 1964, discloses a conventional telescopic type tripot universal joint of the prior art, which has one of the best stroking type universal joints available for osculating engine vibrations from the rest of the vehicle. However, these conventional prior art tripot universal joints due to their operating friction characteristics produce internally generated osculating axial forces which are related to the transmitted torque angles. During severe accelerations at low vehicle speeds these cyclic axial forces can be of sufficient magnitude to produce a shudder type disturbance which has a frequency equal to three times the shaft speed.
To reduce this shudder or vehicle ride disturbance, the generated axial forces must be reduced. This reduction is accomplished by tracking an outer ball or ball assembly of the tripot universal joint relative an axis of the housing. Effective tracking of the outer ball to reduce shudder must have a housing ball bore designated to minimize tipping of the outer or  ball assemble tip  and/or reduce binding of the ball within the track when it does tip. However, ball tip occurs about two axes, the X-axis and Z-axis. The problem with previous designs is the effectiveness at preventing ball tip about the x-axis  X-axis. The inability to prevent ball tip results in increased generated axial forces which lead to shudder. With reference to FIGS. 2, 10 and 11, ball tip about the X-axis (FIGS. 10 and 11) is manifested, particularly when the joint is rotated with axes 18 and 28 non-collinear (FIG. 2), by each annular outer ball 44 of drive roller or ball assembly 16 wobbling or pivoting back and forth about its respective X-axis. In prior tripot universal joints, such wobbling about the X-axis results in the binding of outer ball 44 against side surfaces 22, 24 and guide walls 60 thereof. Referring again to FIGS. 10 and 11, those of ordinary skill in the art will recognize that as the joint is rotated with axes 18 and 28 non-collinear, outer ball 44 pivots about the X-axis at an angle ±θ relative to axis 34 (angle θ correlating to the angle between axes 18 and 28 and the rotational angle of the joint), with the ball alternatingly contacting guide walls 60 on opposite sides of axis 34, at locations axially spaced along the length of each channel 20.